Question

Sets $A$ and $B$ have $3$ and $6$ elements respectively. What can be the minimum number of elements in $A\cup B$

• A. $3$
• B. $6$
• C. $9$
• D. $18$

Answer 1

The correct option is B

$6$

Explanation for the correct option.

Finding the minimum number of elements in $A\cup B$:

Given: Sets $A$ and $B$ have $3$ and $6$ elements respectively.

If all the elements of Set $A$ are different than Set $B$.
Then the maximum number of elements in set $A\cup B$ will be$6+3=9.$
If however, Set $A$ is a subset of $B$, then the total number of elements in set $A\cup B$ will be $=6$.

Hence, the correct answer is option (B)